Meter chamber



Patented Oct. 4, 1932 vireo STATES HARRY G. wEYMonTH AND HoEAo.CHRiSMAN, or PITTSBURGH, PENNSYLVANIA, I

ASSIGNORS To PITTSBURGH EQUITAIBLE METER SYLVANIA, A CORPORATION OIEPENNSYLVANIA PATENT,

coiurerir, or 'rrTTsBUeGn, PENN- METER CHAMBER This invention relates tomeasuring chambers for meters, and particularly to chambers for metersof the nutating disk type.

'These measuring chambers of liquid meters heretofore have usually beencast in two parts that are assembled with their meeting edges in fluidtight engagement. It has been the usual practice to cast the parts ofthe chamber in sand molds and then machine them to size and to providethe necessary close fitting joint between the parts. Many difficultieshave been experienced with these cast metal chambers in liquid metersprincipally because of the inherent porosity of the castings.

The chambers as heretofore used are generally cast from bronze. whichhas been extensively used is composed of alarge proportion of copper,and small equal proportions of lead, zinc and tin. For very many yearsdifliculties were experienced in using such cast metal chambers in themanufacture of fluid meters, and the compositions of the alloys havebeen varied from time to time in efforts to secure castings that did notdeteriorate and disintegrate in the course of time and cause asubstantial change in accuracy of the meter after use for acomparatively short period. These difficulties are believed to belargely due to the fact that cast metal chambers are porous and quicklyaffected by the corrosive action of acid or-alkaline waters or otherliquids which thus materially affect their strength, accuracy anddurability.

Considerable time, thought and money have'been expended in the directionof experimenting and changing the alloys of the materials used in theinternal parts of fluid meters, with the object in view of overcominthese objections, but'onlypartial success has been attained. Theseefforts were made in the belief that the difliculties were due to thealloy used. s

Applicants have discovered that these clifficulties are largely due, notto the nature of the alloys, but principally to the porous nature of thecastings. The meter chamber parts were cast because of their relativelycomplex form, and it has been generally as- One .bronze alloy 1930.Serial N5! 460,975.

sumed that casting the chamber parts was essentialand that improvementscould only be sought in the direction of varying the al: loycompositions. We have found that the meter chambers can be die forgedand we thus do away with defective castings caused by sand, faultyventing, and porous metal; and have found that such chambers have farmore uniformity prior to machining due to elimination 'of theirregularities inherent in sand cast chambers. This makes it unneces:sary torough machine our improved forged chamber. parts. Our die forgedchambers also eliminate the necessity of chipping and filing thechamberports to obtain regularity of said cast chambers.

The measuring chambers as cast from the sand molds heretofore used arefirst subjected to operations of cutting off the gates and risers andthen ground. They are then of the casting to thereby minimize the workto be done by the finishing tool. These first operations are troublesomeand add materially to the cost of the castings. The chambers as cast aredifficult to securely mount in machines on account of their warpedcondition, and the abrasive action of the sand in the castings drillsand wears away the cutting tools, making it necessary to grind and restthe'tool frequently. Sand cast chambers are frequently defective due tocold shots, gas pockets and improperf pouring, and such chambers have tobe discarded. In many instances the defects do not become apparent untilsome of the finishing cuts have been made, so that the loss whensuchdefective density much greater than cast chambers,

liquid meters. The detailed structure thereof and better wearingqualities, making them the necessity for the initial removal of gatesand risers, grounding, sand blasting, pickling, drying, and roughmachining are eliminated. i

The principal object of this invention therefore is to provide a novelmethod of producing the chambers of liquid meters, which is simple andrelatively inexpensive to carry out and in which the chambers producedthereby are superior in every way to the cast chambers heretofore used.

Another object of this invention is to pro-. vide a liquid meter chambermade of a metal alloy whichis less subject to corrosion by acid oralkaline waters, and to provide a chamber made from an alloy, hithertonever used for manufacturing liquid meter chambers, and which readilyadapts itself toa die forging operation. 1 I 7 Further objects of ourinvention are to provide a method of producing the chambers of fluidmeters which is cheaper than the present method, in that there arematerially less chambers discarded as defective, in that the number ofmachining and other operations are greatly reduced, and in that thechambers are more uniform in size and in thickness of the walls.

These and various other objects of our invention will be apparent fromthe follow: ing description and the appended claims when taken inconnection with the accompanying drawing wherein:

Figure 1 is a top plan of the upper portion of a liquid metering chambermade inaccordance with our invention. 7

Figure 2 is a section on line22 of Figure 1.

- Figure 3 is a plan view looking into the bottom chamber.

Figure 1 is a section on line 4:4 of Fig ure 3.

Figure 5 is a side elevation looking into the meter chamber with the twoparts there of assembled. l 7 1 It will be seen that the chamber of aliquid meter as illustrated is similar in general configuration to thatin common use today in however, will be described in order to more fullyemphasize the. various differences between the old form of sand castmeter ng "is provided on its upper surface with anupstanding annularring 2 having tapped holes "3 therein for the reception of screws tohold a disk controlling frame (not shown) in position.

At its center the chamber is provided with a central opening, saidopening being defined by an upper truncatedconical wall 4 and a lowerspherical wall 5. As seen in Figure 2, walls 4 and 5 extend upwardlyfrom the centerof the wall 1 with the upper portionof the wall slightlybelow the plane defined by the upper surface of annular ring 2. Bracingribs 6 connect the annular ring 2 withthe upper. wall at forstrengthening the parts.

The main body portion of the upper cham ber has a downwardly extendingoutwardly spherical wall 7 forming with upper wall 1 a cup-shapedmember. This wall 7 is cut away as .at 8 to provide the upper half of acurved port opening for the assembled chamber. Thedownwardly extendingwall 7 has three lugs 12, 13 and 14 thereon which extend outwardly fromsaid wall and also project slightlyabove the upper portion thereof asseen clearly in Figure 5. i. Lugs12, 13 and 14 have vertical outerfaceswhich are adapted to be positioned in verticalalignment withsimilar faceson lugs of the bottom half of the chamber, these lugscooperating with similarly shaped surfaces on an outer enclosing watermeter casing of .well known construction to position the meteringchamber therein. 1

The outer dependingwall 7 is further provided with a lug 15 which is ofgreater arcuate length than thelugs 12, 13 and 14 to provide adequatebearings around the outlet port, and which has a vertical outer wall 16as. seenin .Figure 5 for further assisting in maintaining the chamberwithin the outer meter casing. Adjacent the lower edge thereof the outerdepending wall 7 is-pro vided with 'anoutstanding ledge 17 which isflush with the outer surfaces of the lugs 12, 13, 14: and15 for thepurpose of reinforcing the chamber edge. and. providing a suitable jointsection;- Thelower edge of the depending wall 7 is provided with aninner groove 18 for cooperative engagement with a similar member on thelower half ofthe chamber. f The upper half of the chamber is providedwith a radial gro ove,21 on the inner surface thereof which grooveextends, inwardly from opening 8 to the central opening provided by thewall 5. seen in Fig positioned therein.

ures 1 and 2, groove 21 extends upwardly through the upper surface ofthe lug 15. This groove 21 is adapted for the reception of a divisionplate for separating opening 8 into an inlet channel an outlet channelfor the chamber. i

Depending wall 7 has a notch 22 cut in the inner surface thereofadjacent lug 13 adapted to receive a thrust roller mounted on a nut tingdisk (not shown) of any well known construction, which ispositioned-within the chamber of an assembled meter. Lug 1% has a hole23 drilled therein from the external surface. Hole 23 adapted to receivepos tioning pin for cooperation with the outer meter casing when thecentral chamber is A depending pin 2st is provided on the lower edge ofthe depending wall 7 for reception in an opening in the lower half ofthe chamber.

The lower half of the chamber is shown in detail in Figures 3 and l andcomprises a cup-shaped member having a. mam conical H c) J \v lvt t 1nah .6 sloping upivai or owait e con el with a central opening dehned bythe spherical wall 27 and the wall of a central opening 28. The lowerhalf of the chamber is provided with lugs 29, 31 and 32 similar to thelugs 12, 13 and i l of the upper half of and in opposite directions.extending wall 39 is provided with a slot 33 the casing and arranged toalign therewith when the chamber is assembled. It will be noted that theouter side surfaces of lugs 12, 1 t, and 29, 32 and 38 incline inwardlyThe upwardly similar to and in alignment with the slot 22 adjacent thelug 13 of the upper chamber, and is further provided with a ring 34 onits lower face, and connected to the outstanding annular ring 35surrounding the central opening 28, said rings 34; and 35 beingconnected by webs 36. r

The lower chamber is further provided on the inner face of wall 26 witha slot 37 which projects downwardly through the lug 38,

which lug corresponds to lug 15 of the upper half of the chamber. Theupperedge of the upstanding wall 39 of the lower chamber is suitablyrabbetted as at 41 for cooperative engagement with inner groove 18 ofthe depending wall 7 of the upper chamber, thus forming a snap joint forthe upper and lower chamber sections.

The wall 39 of the lower chamber is further provided with an openin 42for the reception described in sand molds and then to carry out theoperatlons as above set forth to reduce them to fimshed form for use.These castings have many defects as previously nointed out,

and the casting and manufacturing operations thereon are expensive. Inorder to produce chambers which do not havethe faults of the sand castchambers, we proceed as follows:

One alloy found by careful investigation and research tobe suited fordie forging of inch round bars, and cut off in suitable lengths or diskshaving ust sufficient material in the pieces thereof to make one-half ofthe complete measuring chamber. The disks of the alloy are then heatedto approximately 1250 F. and placed in a drop forging press betweensuitably shaped male and female dies and subjected to pressures of theorder of 600 tons. The male and female dies are of course, carefullymachined to exact size and the metal of thealloy is caused to flowtherein to assumethe shapes shown onthe drawing. The machines for makingup these chambers by a die-forging operation are capable of producingapproximately 50 forgings per minute. r T

When the two halves of the metering chamber come from the die forgingpress, the enormous pressure to which they have been subjected hascaused the metal to be much more dense than the metal of the sand castcally all perfect, since there are no air pockets or holes therein, dueto the fact that the enormous pressures prevent the formation of suchpockets or holes and consequently the discards are eliminated. The wallsof the die forged chambers are uniformly thick at all points and theresultant chamber is strong and rigid, and has many advantages overthesand cast type of chamber. r 7

The invention may be embodied in other specific forms without departingfrom the Chambers made in accordance with th1s lnvention are pract1-'spirit or essential characteristics thereof. The present embodimentistherefore to be considered in all respects as, illustrative and notrestrictive, the scope of the invention being indicated by the appendedclaims rather than by the'foregoing description, and all changes whichcome within the meaning and range of equivalency of the claims aretherefore intended to be embraced therein.

l/Vhat we claim as new and desire to secure by United States LettersPatent is 1. A corrosion-resistant measuring chamber for the nutatingdisk of a liquid meter comprising two mating generally cupshaped brassmembers, said members being separately die forged under high pressure toprovide a hardened'surface of dense texture which is substantiallycorrosion-resistant to acid and alkaline liquids.

2. The invention as defined in claim 1 wherein said members are formedof a brass alloy of approximately 60% copper, 37 70 zinc and 2 lead.

3. A meter chamber consisting of mating generally cup-shaped membersdesigned to be brought together to form said chamber, each memberconsisting of metal having smooth dense non-porous surfaces, saidmembers being adapted for use in meters subject to the action of acid oralkaline fluids.

4. A meter chamber consisting of mating generally cup-shaped membersdesigned to be brought together to form said chamber, each member beingconstructed by a dieforging operation on a suitable brass alloy undersuliicient pressure to cause the surface of each forging to be dense andnon-porous and of sufficient smoothness to enable the forging to be usedas one of said members without roughing cuts.

5. The chamber defined in claim 4 in which said alloy consistsapproximately of copper, 37%% zinc and about 2 lead.

6. A meter chamber consisting of mating members each provided withspherical zones and frusto-conical surfaces and designed to be broughttogether to form said chamber, each member consisting. of metal havingsmooth dense non-porous surfaces, said members being adapted for use inmeters subject to the action of acid or alkaline fluids.

7. A meter chamber consisting of mating generally cup-shaped memberseach provided with spherical zones connected by frustoconical surfacesand designed to be brought together to form said chamber, each memberbeing constructed by a die forging operation on a suitable brass alloyunder sufficient pressure to cause the surface of each forging to bedense and non-porous and of suficient smoothness to enable the forgingto be used as one of said members without roughing cuts 7 8. The chamberdefined in claim 7 in consists approximately of which said alloy copper,37 zinc and about 2 tures.

' HARRY G. WEYMOUTH.

HORACE CHRISMAN.

